Resin bound cellulosic composites such as oriented strand board, particle board, chip board, and plywood are commonly used construction materials and are well known to the art. Resin binders for engineered composites are also well known and include phenol-formaldehyde resins, isocyanate resins, melamine formaldehyde resins, urea formaldehyde resins, and blends containing reactants from one or more of the above reactive resins. The particular resin depends upon the particular manufacturing process used to form the composite, the desired viscosity of the binder, the reaction conditions under which the resin binder is to cure, and the amount of moisture that may be in the cellulosic material used. Many of these composites are exposed to moisture during storage, use, and/or during construction so it is desirable that the moisture not change the shape, appearance, or structural integrity of the composite.
Many of these resin binders include small amounts of wax to make the resin binder, along with the entire composite, more hydrophobic (moisture repellant). The wax additives tend to spread on the surface of the composites and give improved water resistance. However the wax can be migratory which leads to problems with the hydrophobic surface nature of the composite being lost or reduced. It is also possible for the wax to be ineffectively dispersed which can result in unacceptably low hydrophobicity and/or lesser physical strength and integrity in the composite.